LoongArch: KVM: Add EIOINTC user mode read and write functions

Implement the communication interface between the user mode programs
and the kernel in EIOINTC interrupt controller simulation, which is
used to obtain or send the simulation data of the interrupt controller
in the user mode process, and is also used in VM migration or VM saving
and restoration.

Signed-off-by: Xianglai Li <lixianglai@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Author: lixianglai

arch/loongarch/include/uapi/asm/kvm.h

@@ -134,4 +134,16 @@ struct kvm_iocsr_entry {
 
 #define KVM_DEV_LOONGARCH_IPI_GRP_REGS			0x40000001
 
+#define KVM_DEV_LOONGARCH_EXTIOI_GRP_REGS		0x40000002
+
+#define KVM_DEV_LOONGARCH_EXTIOI_GRP_SW_STATUS		0x40000003
+#define KVM_DEV_LOONGARCH_EXTIOI_SW_STATUS_NUM_CPU	0x0
+#define KVM_DEV_LOONGARCH_EXTIOI_SW_STATUS_FEATURE	0x1
+#define KVM_DEV_LOONGARCH_EXTIOI_SW_STATUS_STATE	0x2
+
+#define KVM_DEV_LOONGARCH_EXTIOI_GRP_CTRL		0x40000004
+#define KVM_DEV_LOONGARCH_EXTIOI_CTRL_INIT_NUM_CPU	0x0
+#define KVM_DEV_LOONGARCH_EXTIOI_CTRL_INIT_FEATURE	0x1
+#define KVM_DEV_LOONGARCH_EXTIOI_CTRL_LOAD_FINISHED	0x3
+
 #endif /* __UAPI_ASM_LOONGARCH_KVM_H */

arch/loongarch/kvm/intc/eiointc.c

@@ -781,16 +781,175 @@ static const struct kvm_io_device_ops kvm_eiointc_virt_ops = {
 	.write	= kvm_eiointc_virt_write,
 };
 
+static int kvm_eiointc_ctrl_access(struct kvm_device *dev,
+					struct kvm_device_attr *attr)
+{
+	int ret = 0;
+	unsigned long flags;
+	unsigned long type = (unsigned long)attr->attr;
+	u32 i, start_irq;
+	void __user *data;
+	struct loongarch_eiointc *s = dev->kvm->arch.eiointc;
+
+	data = (void __user *)attr->addr;
+	spin_lock_irqsave(&s->lock, flags);
+	switch (type) {
+	case KVM_DEV_LOONGARCH_EXTIOI_CTRL_INIT_NUM_CPU:
+		if (copy_from_user(&s->num_cpu, data, 4))
+			ret = -EFAULT;
+		break;
+	case KVM_DEV_LOONGARCH_EXTIOI_CTRL_INIT_FEATURE:
+		if (copy_from_user(&s->features, data, 4))
+			ret = -EFAULT;
+		if (!(s->features & BIT(EIOINTC_HAS_VIRT_EXTENSION)))
+			s->status |= BIT(EIOINTC_ENABLE);
+		break;
+	case KVM_DEV_LOONGARCH_EXTIOI_CTRL_LOAD_FINISHED:
+		eiointc_set_sw_coreisr(s);
+		for (i = 0; i < (EIOINTC_IRQS / 4); i++) {
+			start_irq = i * 4;
+			eiointc_update_sw_coremap(s, start_irq,
+					(void *)&s->coremap.reg_u32[i], sizeof(u32), false);
+		}
+		break;
+	default:
+		break;
+	}
+	spin_unlock_irqrestore(&s->lock, flags);
+
+	return ret;
+}
+
+static int kvm_eiointc_regs_access(struct kvm_device *dev,
+					struct kvm_device_attr *attr,
+					bool is_write)
+{
+	int addr, cpuid, offset, ret = 0;
+	unsigned long flags;
+	void *p = NULL;
+	void __user *data;
+	struct loongarch_eiointc *s;
+
+	s = dev->kvm->arch.eiointc;
+	addr = attr->attr;
+	cpuid = addr >> 16;
+	addr &= 0xffff;
+	data = (void __user *)attr->addr;
+	switch (addr) {
+	case EIOINTC_NODETYPE_START ... EIOINTC_NODETYPE_END:
+		offset = (addr - EIOINTC_NODETYPE_START) / 4;
+		p = &s->nodetype.reg_u32[offset];
+		break;
+	case EIOINTC_IPMAP_START ... EIOINTC_IPMAP_END:
+		offset = (addr - EIOINTC_IPMAP_START) / 4;
+		p = &s->ipmap.reg_u32[offset];
+		break;
+	case EIOINTC_ENABLE_START ... EIOINTC_ENABLE_END:
+		offset = (addr - EIOINTC_ENABLE_START) / 4;
+		p = &s->enable.reg_u32[offset];
+		break;
+	case EIOINTC_BOUNCE_START ... EIOINTC_BOUNCE_END:
+		offset = (addr - EIOINTC_BOUNCE_START) / 4;
+		p = &s->bounce.reg_u32[offset];
+		break;
+	case EIOINTC_ISR_START ... EIOINTC_ISR_END:
+		offset = (addr - EIOINTC_ISR_START) / 4;
+		p = &s->isr.reg_u32[offset];
+		break;
+	case EIOINTC_COREISR_START ... EIOINTC_COREISR_END:
+		offset = (addr - EIOINTC_COREISR_START) / 4;
+		p = &s->coreisr.reg_u32[cpuid][offset];
+		break;
+	case EIOINTC_COREMAP_START ... EIOINTC_COREMAP_END:
+		offset = (addr - EIOINTC_COREMAP_START) / 4;
+		p = &s->coremap.reg_u32[offset];
+		break;
+	default:
+		kvm_err("%s: unknown eiointc register, addr = %d\n", __func__, addr);
+		return -EINVAL;
+	}
+
+	spin_lock_irqsave(&s->lock, flags);
+	if (is_write) {
+		if (copy_from_user(p, data, 4))
+			ret = -EFAULT;
+	} else {
+		if (copy_to_user(data, p, 4))
+			ret = -EFAULT;
+	}
+	spin_unlock_irqrestore(&s->lock, flags);
+
+	return ret;
+}
+
+static int kvm_eiointc_sw_status_access(struct kvm_device *dev,
+					struct kvm_device_attr *attr,
+					bool is_write)
+{
+	int addr, ret = 0;
+	unsigned long flags;
+	void *p = NULL;
+	void __user *data;
+	struct loongarch_eiointc *s;
+
+	s = dev->kvm->arch.eiointc;
+	addr = attr->attr;
+	addr &= 0xffff;
+
+	data = (void __user *)attr->addr;
+	switch (addr) {
+	case KVM_DEV_LOONGARCH_EXTIOI_SW_STATUS_NUM_CPU:
+		p = &s->num_cpu;
+		break;
+	case KVM_DEV_LOONGARCH_EXTIOI_SW_STATUS_FEATURE:
+		p = &s->features;
+		break;
+	case KVM_DEV_LOONGARCH_EXTIOI_SW_STATUS_STATE:
+		p = &s->status;
+		break;
+	default:
+		kvm_err("%s: unknown eiointc register, addr = %d\n", __func__, addr);
+		return -EINVAL;
+	}
+	spin_lock_irqsave(&s->lock, flags);
+	if (is_write) {
+		if (copy_from_user(p, data, 4))
+			ret = -EFAULT;
+	} else {
+		if (copy_to_user(data, p, 4))
+			ret = -EFAULT;
+	}
+	spin_unlock_irqrestore(&s->lock, flags);
+
+	return ret;
+}
+
 static int kvm_eiointc_get_attr(struct kvm_device *dev,
 				struct kvm_device_attr *attr)
 {
-	return 0;
+	switch (attr->group) {
+	case KVM_DEV_LOONGARCH_EXTIOI_GRP_REGS:
+		return kvm_eiointc_regs_access(dev, attr, false);
+	case KVM_DEV_LOONGARCH_EXTIOI_GRP_SW_STATUS:
+		return kvm_eiointc_sw_status_access(dev, attr, false);
+	default:
+		return -EINVAL;
+	}
 }
 
 static int kvm_eiointc_set_attr(struct kvm_device *dev,
 				struct kvm_device_attr *attr)
 {
-	return 0;
+	switch (attr->group) {
+	case KVM_DEV_LOONGARCH_EXTIOI_GRP_CTRL:
+		return kvm_eiointc_ctrl_access(dev, attr);
+	case KVM_DEV_LOONGARCH_EXTIOI_GRP_REGS:
+		return kvm_eiointc_regs_access(dev, attr, true);
+	case KVM_DEV_LOONGARCH_EXTIOI_GRP_SW_STATUS:
+		return kvm_eiointc_sw_status_access(dev, attr, true);
+	default:
+		return -EINVAL;
+	}
 }
 
 static int kvm_eiointc_create(struct kvm_device *dev, u32 type)